SAT Prep | Prefixes
| PREFIX | MEANING | EXAMPLE |
| ab—, a—, abs— | away, without, from | absent — away, not present apathy — without interest abstain — keep from doing, refrain |
| ad— | to, toward | adjacent — next to address — to direct toward |
| ante— | before | antecedent — going before in time anterior — occurring before |
| anti— | against | antidote — remedy to act against an evil antibiotic — substance that fights against bacteria |
| be— | over, thouroughly | bemoan — to mourn over belabor — to exert much labor upon |
| bi— | two | bisect — to divide biennial — happening every two years |
| cata—, cat—, cath— | down | catacombs — underground passageways catalogue — descriptive list catheter — tubular medical device |
| circum— | around | circumscribe — to draw a circle around circumspect — watchful on all sides |
| com— | with | combine — to join together communication — to have dealings with |
| contra— | against | contrary — opposed contrast — to stand in opposition |
| de— | down, from | decline — to bend downward decontrol — to release from government control |
| di— | two | dichotomy — cutting in two diarchy — system of government with two authorities |
| dis—, di— | apart, away | discern — to distinguish as separate dismiss — to send away digree — to turn aside |
| epi—, ep—, eph— | upon, among | epidemic — happening among many people epicycle — circle whose center moves around in the circumference of a greater circle epaulet — decoration worn to ornament or protect the shoulder ephedra — any of a large genus of desert shrubs |
| ex—, e— | from, out | exceed — go beyond the limit emit — to send forth |
| extra— | outside, beyond | extraordinary — beyond or out of the common method extrasensory — beyond the senses |
| hyper— | beyond, over | hyperactive — over the normal activity level hypercritic — one who is critical beyond measure |
| hypo— | beneath, lower | hypodermic — parts beneath the skin hypocrisy — to be under a pretense of goodness |
| in—, il—, im—, ir— | not | inactive — not active illogical — not logical imperfect — not perfect irreversible — not reversible |
| in—, il—, im—, ir— | in, on, into | instill — to put in slowly illation — action of bringing in impose — to lay on irrupt — to break in |
| inter— | among, between | intercom — to exchange conversations between people interlude — performance given between parts in a play |
| intra— | within | intravenous — within a vein intramural — within a single college or its students |
| meta— | beyond, over, along with | metamorphosis — change over in form or nature metatarsus — part of the foot beyond the flat of the foot |
| mis— | badly, wrongly | misconstrue — to interpret wrongly misappropriate — to use wrongly |
| mono— | one | monogamy — to be married to one person at a time monotone — a single, unvaried tone |
| multi— | many | multiple — of many parts multitude — a great number |
| non— | no, not | nonsense — lack of sense nonentity — not existing |
| ob— | against | obscene — offensive to modesty obstruct — to hinder the passage of |
| para—, par— | beside | parallel — continuously at equal distance apart parenthesis — sentence inserted within a passage |
| per— | through | persevere — to maintain an effort permeate — to pass through |
| poly— | many | polygon — a plane figure with many sides or angles polytheism — belief in the existence of many gods |
| post— | after | posterior — coming after postpone — to put off until a future time |
| pre— | before | premature — ready before the proper time premonition — a previous warning |
| pro— | in favor of, forward | prolific — bringing forth offspring project — throw or cast forward |
| re— | back, against | reimburse — to pay back retract— to draw back |
| semi— | half | semicircle — half a circle semiannual — half-yearly |
| sub— | under | subdue — to bring under one's power submarine — to travel under the surface of the sea |
| super— | above | supersonic — above the speed of sound superior — higher in place or position |
| tele—, tel— | across | telecast — transmit across a distance telepathy — communication between mind and mind at a distance |
| trans— | across | transpose — to change the position of two things transmit — to send from one person to another |
| ultra— | beyond | ultraviolet — beyond the limit of visibility ultramarine — beyond the sea |
| un— | not | undeclared — not declared unbelievable — not believable |
| uni— | one | unity — state of oneness unison — sounding together |
| with— | away, against | withhold — to hold back withdraw — to take away |
